TY - JOUR A1 - Abad Andrade, Carlos Enrique A1 - Jegielka, Dennis A1 - Aloysius, Allen A1 - Recknagel, Sebastian T1 - SI-traceable total analysis of nitrate and nitrite by isotope dilution optical spectroscopy and its application to Berlin surface waters N2 - Accurate nitrate and nitrite data support water-quality regulation, yet routine methods rely on external calibration and rarely achieve SI traceability. We report a calibration-free determination of nitrate and nitrite by combining isotope dilution with high-resolution continuum-source graphite furnace molecular absorption spectrometry (ID-HR-CS-GF-MAS). A 15N-enriched nitrate spike (its concentration verified by reverse isotope dilution against the standard reference material NIST 3185) provides the SI link, and it is gravimetrically added to samples; nitrate and residual nitrite are converted in situ to nitric oxide (NO), whose 215 nm band is recorded at a pixel resolution of λ/Δλ ≈ 140 000. The 0.2127 nm shift between 14NO and 15NO electronic spectra is resolved, and a three-latent-variable partial least squares regression model yields the 15N/14N ratio with 0.3% precision. Instrumental LoD values of 4.8 ng (14N) and 3.2 ng (15N) translate to a method LoD of 4.8 ng of nitrogen (equivalent to 1.05 mg L−1 NO3− for a 20 μL aliquot). The furnace program allows for successive drying/pyrolysis loops, so additional 20 μL aliquots can be layered onto the graphite platform. Alternatively, a 10 mL anion-exchange solid-phase extraction step concentrates nitrate and nitrite fivefold, allowing for the analysis of even lower sample concentrations. Results for four certified reference materials (2.9 to 1000 mg L−1 NO3−) agreed with certified values, giving relative expanded uncertainties of 2 to 4%. Analysis of twenty Berlin surface-water samples revealed concentrations ranging from 0.10 to 7.3 mg L−1 NO3−, indicating that the Panke River and Teltow Canal are the primary sources of nitrogen. ID-HR-CS-GF-MAS thus delivers ID-MS-level accuracy in a few minutes per run with bench-top optics, and, with optional on-platform or SPE pre-concentration, extends SI-traceable nitrate/nitrite monitoring into the low-ng regime. KW - Isotope dilution KW - Nitrate and nitrite determination KW - SI-traceable quantification KW - Calibration-free analysis KW - Water quality KW - Berlin surface waters KW - NO molecular absorption bands PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-643785 DO - https://doi.org/10.1039/D5JA00252D SN - 0267-9477 VL - 40 IS - 10 SP - 2692 EP - 2701 PB - Royal Society of Chemistry (RSC) AN - OPUS4-64378 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Klinge, A A1 - Mönig, J A1 - Ziegert, C A1 - Richter, Matthias A1 - Kalbe, Ute A1 - Horn, Wolfgang A1 - Röhlen, U A1 - Rauscher, S A1 - Roswag-Klinge, E T1 - upMIN 100 – upcycling of mineral construction and demolition waste to substitute natural aggregates in earthen building materials N2 - The construction sector is one of the most resource-intensive sectors in Germany and is responsible for 40 % of CO2 emissions. Around 517 million tons of mineral raw materials are required annually for the construction of buildings in Germany. At the same time, mineral construction waste was the largest material flow at 229.3 million tons (2020). The rates of construction and demolition waste (CDW) recycling have increased since 2000, especially for mineral waste. Nevertheless, the majority of recycled aggregates are used in technically largely unregulated applications (e.g. road construction). This downcycling leads to a loss of valuable resources for technically and economically valuable applications. The upMIN 100 research project is investigating the question of whether and to what extent recycled CDW is suitable as an additive an binder in earthen building materials. The focus is placed on grain sizes of < 2 mm, which are currently predominantly landfilled, as there are at present no regulations for their use in building products. The soil matrix of earthen building materials however, naturally contains of different grain sizes, whith < 2mm – 0,063 for aggregates and < 0.063 mm as a binder. Therefore, the focused grain sizes (sand, clay and silt) could have a high usage potential. In order to enable the use of CDW, the technical feasibility must be ensured, quality requirements for source materials (e.g. threshold values for pollutants in terms of health and environmental compatibility and hazardous substances) and permissible proportions of recycled aggregates must be defined. Two different building material developments (earth blocks and -plaster)were used to assess both, the technical feasibility as well the pollutant content of the recycled aggregate and its final emissions into the indoor air. For both materials two mixtures could be established, that also meet the mechanical specifications according to the DIN standard, such as the compressive strength. A method was developed to design material mixtures with a high amount of CDW that comply with the defined limit values. The mixtures reached a recycling rate of 28 % with high mechanical properties and 70 % with minimum strength requirements. KW - Mineral waste KW - Upcycling KW - Earthen building product KW - Circular construction PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-652831 DO - https://doi.org/10.1088/1755-1315/1554/1/012084 SN - 1755-1307 VL - 1554 IS - 1 SP - 1 EP - 9 PB - IOP Publishing AN - OPUS4-65283 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Chapartegui-Arias, Ander A1 - Raysyan, A. A1 - Belenguer, A. M. A1 - Jaeger, Carsten A1 - Tchipilov, Teodor A1 - Prinz, Carsten A1 - Abad Andrade, Carlos Enrique A1 - Beyer, S. A1 - Schneider, Rudolf A1 - Emmerling, Franziska T1 - Tailored mobility in a zeolite imidazolate framework (ZIF) antibody conjugate N2 - Zeolitic imidazolate framework (ZIF) hybrid fluorescent nanoparticles and ZIF antibody conjugates have been synthesized, characterized, and employed in lateral-flow immunoassay (LFIA). The bright fluorescence of the conjugates and the possibility to tailor their mobility gives a huge potential for diagnostic assays. An enzyme-linked immunosorbent assay (ELISA) with horseradish peroxidase (HRP) as label, proved the integrity, stability, and dispersibility of the antibody conjugates, LC-MS/MS provided evidence that a covalent link was established between these metal-organic frameworks and lysine residues in IgG antibodies. KW - ZIF KW - ELISA PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-532096 DO - https://doi.org/10.1002/chem.202100803 SN - 0947-6539 SN - 1521-3765 VL - 27 IS - 36 SP - 9414 EP - 9421 PB - Wiley-VCH CY - Weinheim AN - OPUS4-53209 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tuma, Dirk A1 - Mady, A. H. A1 - Baynosa, M. L. A1 - Saad, M. A1 - Dhakal, G. A1 - Kim, W. K. A1 - Shim, Jae-Jin T1 - Morphology-engineered hollow NiTiO₃/C–Ag/Ag₃PO₄ S-scheme heterojunction photocatalyst: mechanistic insights into sunlight-driven tetracycline degradation N2 - Tetracycline (TCH), a widely used antibiotic, persists in aquatic and terrestrial environments, posing ecological risks and accelerating antibiotic resistance. To address this, we report a hollow-structured NiTiO₃/C–Ag/Ag₃PO₄ (NT/C–AAP) photocatalyst—the first hollow-type nickel titanate—synthesized via a self-template solvothermal route followed by photodeposition. The catalyst integrates key design strategies—hollow architecture, oxygen vacancies, carbon coating, and an S-scheme heterojunction—to optimize photocatalytic performance. The hollow structure enhances light harvesting via internal scattering, oxygen vacancies facilitate O2 adsorption and superoxide (O₂•⁻) generation, and the S-scheme heterojunction effectively suppresses electron–hole recombination while preserving strong redox potential. NT/C–AAP achieved 96% TCH degradation within 1 h and 82% mineralization in 3 h under solar light, far exceeding core–shell (18%) and aggregated (47%) NiTiO₃-based catalysts. Complete removal was realized within 40 min under 400 W visible light. The catalyst maintained 96% activity after five cycles, confirming excellent durability. Compared with previously reported NiTiO₃ photocatalysts, NT/C–AAP delivered a 50–400% performance enhancement arising from its engineered hollow structure and improved electronic properties. Mechanistic studies identified O₂•⁻ and •OH radicals as dominant species, validating the role of morphology and interface engineering in directing charge separation and redox activity. Additionally, a catalyst performance index was proposed to facilitate comparison across diverse conditions. Overall, this work introduces a novel, durable photocatalyst that links structural design to functional performance and demonstrates strong potential for practical environmental remediation. KW - Heterojunction photocatalyst KW - Photodegradation KW - Tetracycline PY - 2026 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-655946 DO - https://doi.org/10.1007/s42114-025-01600-x SN - 2522-0128 VL - 9 IS - 2 SP - 1 EP - 19 PB - Springer Nature CY - London AN - OPUS4-65594 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Battistella, Beatrice A1 - Revill, Adam A1 - Venzago, Cornel A1 - Hoffmann, Volker A1 - Agudo Jácome, Leonardo A1 - Al-Sabbagh, Dominik A1 - Recknagel, Sebastian A1 - Abad, Carlos T1 - Depth-Resolved Lithium Isotope Fractionation as a Diagnostic of Interphase Evolution and Degradation in Lithium-Ion Batteries N2 - Lithium isotopic fractionation is well-established in dynamic geochemical systems; however, its role in lithium-ion batteries (LIBs) remains uninvestigated. Herein, we report the first depth-resolved demonstration that isotopic separation occurs during Li-ion cell operation whose magnitude depends on the cycling history. Using depth-resolved glow discharge mass spectrometry, we monitored the 7Li/6Li ratio in LiNi0.333Mn0.333Co0.333O2 (NMC111)||graphite coin cell electrodes at defined life-cycle stages. Different charging rates were examined to get mechanistic insight into kinetic and thermodynamic control in the fractionation process. Although pristine electrodes exhibit a uniform isotopic ratio, cycled electrodes show a distinct 7Li enrichment in the positive electrode and a corresponding accumulation of 6Li at the surface of the negative electrode. The degree of isotopic separation varies with the charging rate. Isotopic signatures correlate with capacity fading, indicating lithium isotope mapping as a sensitive diagnostic tool for tracking electrode degradation and the evolution of the electrode–electrolyte interphases in LIBs. KW - Lithium-Ion Battery KW - Li Isotopes KW - Glow Discharge Mass Spectrometry GD-MS PY - 2026 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-657229 DO - https://doi.org/10.1021/acsenergylett.5c0413737 SN - 2380-8195 VL - 11 IS - 3 SP - 2851 EP - 2857 PB - ACS Publications AN - OPUS4-65722 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Richter, Matthias A1 - Baldan, A. A1 - Beelen, R. A1 - de Boed, E. J.J. A1 - Tuma, Dirk A1 - Kipphardt, Heinrich A1 - Wilke, Olaf A1 - van der Veen, A. M.H. T1 - Primary gas standards for the determination of sulfur-based impurities at trace level in hydrogen N2 - Hydrogen fuel quality needs to comply with ISO 14687:2025 to avoid harmful impact on applications using proton-exchange membrane (PEM) fuel cells. For total sulfur as one of the most impactful contaminants, an amount fraction of 4 nmol/mol has been set as threshold (so-called Grade D quality). In this study, novel gaseous primary gas standards (PGS) of seven sulfur compounds were prepared either gravimetrically at 1000 nmol/mol, 100 nmol/mol, and 10 nmol/mol, or dynamically diluted down to 4 nmol/mol in hydrogen and argon matrices with relative expanded uncertainties well below 10 % (k = 2) and proven stability of at least 9–12 months. Two different cylinder passivation treatments were compared, with one treatment identified as unsuitable since reactions took place within the mixture. By performing a cross-check study, equivalence between both sets of PGS could be demonstrated (≤ 5 % relative deviation for most of the sulfur species). KW - Hydrogen quality KW - ISO 14687 KW - Sulfur impurities KW - Primary gas standards KW - TD-GC/SCD PY - 2026 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-656759 DO - https://doi.org/10.1016/j.ijhydene.2026.154461 SN - 0360-3199 VL - 224 SP - 1 EP - 13 PB - Elsevier Ltd. AN - OPUS4-65675 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bayat, Mehmet Emin A1 - Nandayapa, Edgar R. A1 - Tiebe, Carlo A1 - Unger, Eva L. A1 - List-Kratochvil, Emil J. W. T1 - An operando spectroscopic examination of the influence of trace humidity on interdigital back contact metal halide perovskite solar cells N2 - Controlling trace humidity is vital for both the fabrication and long-term stability of metal halide perovskite (MHP) solar cells. Relevant humidity levels are typically below 10 ppmV, especially in glovebox-based processing and in well-encapsulated devices. Even minute amounts during fabrication can influence crystallization, introducing defects and lowering efficiency. Over time, humidity accelerates degradation of the perovskite layer and internal interfaces, ultimately reducing operational lifetime. Probing these effects at low concentrations under operando conditions is therefore essential for advancing device performance and durability. In this work, we employed a high-precision transfer standard dew point hygrometer to investigate humidity levels between 5 and 35 ppmV in non-encapsulated MHP solar cells. To permit unobstructed water migration during operation, we fabricated interdigital back contact devices. Operando measurements revealed water transport through the perovskite layer and enabled quantification of outgassing. Under trace-humidified conditions, devices exhibited initial charge-carrier quenching, followed by gradual recovery. Notably, the photocurrent response to humidified nitrogen demonstrated that the MHP layer behaves fully reversibly within the explored timescale and across the investigated humidity levels and conditions. These findings establish a systematic operando framework for examining extrinsic stressors in perovskites and highlight opportunities for assessing passivation strategies. KW - Metal halide perovskite KW - IBC solar cells KW - In operando KW - Extrinsic stressors KW - Fabrication and encapsulation KW - Trace humidity KW - Two-site Stern-Volmer KW - Charge-carrier quenching PY - 2026 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-657560 DO - https://doi.org/10.1039/D6TA01295G SP - 1 EP - 16 PB - The Royal Society of Chemistry CY - London AN - OPUS4-65756 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -